1. Field of the Invention
The present invention relates generally to earth cultivation methods and apparatus. More particularly, the present invention relates to a seedbed preparation method and apparatus operable where minimum tillage is desired of soil covered by residue from previous plantings.
Such minimum tillage systems require fewer passes over the soil by farming machinery, resulting in several advantages to the farmer.
The soil is less compacted, and therefore presents a better seedbed to promote plant growth. The looser soil retains moisture better, prevents run off, and provides for better root growth. Further, by leaving previous planting residue largely undisturbed, a protective covering for the soil is provided which increases water absorption and decreases weed growth. Still further, fewer passes over the field represents an obvious savings in manhours and operating costs.
The present invention allows a farmer to cultivate and fertilize the soil and plant seed in one pass over a residue-covered field by adding a paired fluted coulter assembly to pre-existing seed planting machinery.
2. Description of the Relevant Art
Various minimum till or no till planting devices are known. However, these devices are all integrated systems which do not contemplate the simple addition of the seedbed preparation assembly to the front of an ordinary seed planting unit. Such conventionally known systems are exemplified by the following.
Italian Pat. No. 525,840, issued in 1955, discloses a seeding machine capable of depositing fertilizer to different layers of soil. The apparatus is capable of concurrently breaking soil and disposing fertilizer at two distinct depths. The apparatus is comprised of a central frame assembly having at its leading portion a pivotable wheel assembly, and at its trailing portion a fixed trail roller. The frame is further fitted with fertilizer storage tanks and a number of blade/feeder extensions communicating with the base for each fertilizer storage tank. The blade/feeder extensions have two lengths, thus allowing the soil to be broken and fertilized at two depths.
Morrison, Jr. U.S. Pat. No. 3,362,361, entitled "PLANTING METHOD AND APPARATUS", discloses an in-line assembly having a forward pair of plain (as opposed to fluted) residue-removing discs, a trench-pressing wheel, a seed-distributing mechanism, a wheel to press seeds into the ground, and a following pair of plain covering discs to push earth over the seeds. Offset to one side is a fertilizer trench cutter and placement assembly. All of these components are supported off a central frame.
Krumholz U.S. Pat. No. 3,701,327, entitled "PLANTER AND METHOD OF PREPARING SOIL", discloses a fertilizer and planter assembly having a single forward-mounted fluted coulter for cultivation and residue removal. The Krumholz patent also includes the coulter and fertilizer elements as parts of a central frame apparatus. The Krumholz patent does not disclose any specific mounting or biasing assembly for the coulter unit in relation to the main frame assembly, nor the use of a dual coulter assembly for increased soil preparation efficiency.
Hardin et al. U.S. Pat. No. 4,187,916, entitled "SOIL CONDITIONING AND SEED BED PREPARING APPARATUS", discloses a main frame assembly having a subsoil trenching blade with following fertilizer delivery tube and a trench filling fluted coulter wheel. Mounted to the front of the main frame by unequal length control arms is a fluted coulter with exposed spring biasing means. On the rear of the main frame is mounted a flex arm on each side of which is mounted a fluted coulter assembly with a variety or adjustment means. The coulter assembly itself contains no biasing spring. The Hardin et al. patent does not disclose the optimal spatial relationship between the offset fluted coulter wheels, but merely indicates that such offset will prevent clogging of the assembly. The Hardin et al. patent further contemplates that a conventional seed planting mechanism will be attached to and pulled behind the entire soil conditioning and seedbed preparation apparatus.
Peterson et al. U.S. Pat. No. 4,244,306, entitled "MINIMUM TILLAGE PLANTER", discloses an apparatus for seeding of land which has been previously harvested. The apparatus comprises a wheeled framework supporting the apparatus for movement about a field. At the front of the framework is a row of chisels which produce tilled areas parallel to the path of movement of the framework. Each chisel carries a roller which breaks up any resulting clods of soil. Liquid fertilizer is directed to the tilled areas by delivering conduits extending along the rear of each chisel to their respective lower ends. Affixed on the rear of the Peterson frame is a seed distribution apparatus.
The problem with the current devices is that they do not provide an easily adjustable, self-contained seedbed preparation apparatus which is independently mountable to existing planting device frames. The present invention, by front mounting the paired coulter seedbed preparation assembly to an existing seed planting apparatus solves these problems with a low cost, high efficiency apparatus.